Postoperative Radiotherapy in Stage I-III Merkel Cell Carcinoma

BACKGROUND: Postoperative radiotherapy (PORT) is currently recommended for the treatment of Merkel cell carcinoma. Nevertheless, deviations occur frequently due to the generally elderly and frail patient population. We aimed to evaluate the influence of PORT on survival in stage I-III MCC patients treated in the Netherlands. METHODS: Patients were included retrospectively between 2013 and 2018. Fine-Gray method was used for cumulative incidence of recurrence and MCC-related survival, cox regression was performed for overall survival (OS). Analyses were performed in patients with clinical (sentinel node biopsy [SN] not performed) stage I/II (c-I/II-MCC), pathologic (SN negative) stage I/II (p-I/II-MCC) and stage III MCC (III-MCC), separately. Propensity score matching (PSM) was performed to assess confounding by indication. RESULTS: In total 182 patients were included, 35 had p-I/II-MCC, 69 had c-I/II-MCC and 78 had III-MCC. Median follow up time was 53.5 (IQR 33.4-67.4), 30.5 (13.0-43.6) and 29.3 (19.3-51.0) months, respectively. Multivariable analysis showed PORT to be associated with less recurrences and improved OS, but not with MCC-related survival. In stage III-MCC, extracapsular extension (sub-distribution hazard [SDH] 4.09, p=0.012) and PORT (SDH 0.45, p=0.044) were associated with recurrence, and ≥4 positive lymph nodes (SDH 3.24, p=0.024) were associated with MCC-related survival. CONCLUSIONS: PORT was associated with less recurrences and improved OS in patients with stage I-III MCC, but not with improved MCC-related survival. Trends in OS benefit are likely to be caused by selection bias suggesting further refinement of criteria for PORT is warranted, for instance by taking life expectancy into account

Surgery for unresectable stage IIIC and IV melanoma in the era of new systemic therapy

Opportunities for surgical treatment in metastatic melanoma patients have re-emerged due to the development of novel systemic therapeutics over the past decade. The aim of this study is to present data on outcomes of surgery in patients with unresectable stage IIIC and IV melanoma, who have previously been treated with immunotherapy or targeted therapy. Data was extracted from the Dutch Melanoma Treatment Registry (DMTR) on 154 patients obtaining disease control to systemic therapy and undergoing subsequent surgery. Disease control was defined as a complete response (CR), which was seen in 3.2% of patients; a partial response (PR), seen in 46.1% of patients; or stable disease (SD), seen in 44.2% of patients. At a median follow-up of 10.0 months (interquartile range 4-22) after surgery, the median overall survival (OS) had not been reached in our cohort and median progression-free survival (PFS) was 9.0 months (95% CI 6.3-11.7). A CR or PR at first follow-up after surgery was associated with both a better OS and PFS compared to stable or progressive disease (p < 0.001). We conclude that selected patients can benefit from surgery after achieving disease control with systemic therapy

Is a History of Optimal Staging by Sentinel Lymph Node Biopsy in the Era Prior to Adjuvant Therapy Associated with Improved Outcome Once Melanoma Patients have Progressed to Advanced Disease?

Introduction: Sentinel lymph node biopsy (SLNB) is important for staging in patients with primary cutaneous melanoma. Did having previously undergone SLNB also affect outcomes in patients once they have progressed to metastatic melanoma in the era prior to adjuvant therapy?Methods: Data were retrieved from the Dutch Melanoma Treatment Registry, a prospectively collected, nationwide database of patients with unresectable stage IIIC or IV (advanced) melanoma between 2012 and 2018. Melanoma-specific survival (MSS) was compared between patients with advanced cutaneous melanoma, previously treated with a wide local excision (WLE) or WLE combined with SLNB as initial treatment of their primary tumor. Cox regression analyses were used to analyze the influence of different variables on MSS.Results: In total, 2581 patients were included, of whom 1412 were treated with a WLE of the primary tumor alone and 1169 in whom this was combined with SLNB. At a median follow-up of 44 months from diagnosis of advanced melanoma, MSS was significantly longer in patients who had previously undergone SLNB {median 23 months (95% confidence interval [CI] 19–29) vs. 18 months (95% CI 15–20) for patients treated with WLE alone; p = 0.002}. However, multivariate Cox regression did not identify SLNB as an independent favorable prognostic factor for MSS after diagnosis of advanced melanoma.Conclusion: Prior to the availability of adjuvant systemic therapy, once patients have unresectable stage IIIC or IV (advanced) melanoma, there was no difference in disease outcome for patients who were or were not previously staged with SLNB.</p

Reversal of pre-existing NGFR-driven tumor and immune therapy resistance

Melanomas can switch to a dedifferentiated cell state upon exposure to cytotoxic T cells. However, it is unclear whether such tumor cells pre-exist in patients and whether they can be resensitized to immunotherapy. Here, we chronically expose (patient-derived) melanoma cell lines to differentiation antigen-specific cytotoxic T cells and observe strong enrichment of a pre-existing NGFRhi population. These fractions are refractory also to T cells recognizing non-differentiation antigens, as well as to BRAF + MEK inhibitors. NGFRhi cells induce the neurotrophic factor BDNF, which contributes to T cell resistance, as does NGFR. In melanoma patients, a tumor-intrinsic NGFR signature predicts anti-PD-1 therapy resistance, and NGFRhi tumor fractions are associated with immune exclusion. Lastly, pharmacologic NGFR inhibition restores tumor sensitivity to T cell attack in vitro and in melanoma xenografts. These findings demonstrate the existence of a stable and pre-existing NGFRhi multitherapy-refractory melanoma subpopulation, which ought to be eliminated to revert intrinsic resistance to immunotherapeutic intervention

Surgery for Unresectable Stage IIIC and IV Melanoma in the Era of New Systemic Therapy

Opportunities for surgical treatment in metastatic melanoma patients have re-emerged due to the development of novel systemic therapeutics over the past decade. The aim of this study is to present data on outcomes of surgery in patients with unresectable stage IIIC and IV melanoma, who have previously been treated with immunotherapy or targeted therapy. Data was extracted from the Dutch Melanoma Treatment Registry (DMTR) on 154 patients obtaining disease control to systemic therapy and undergoing subsequent surgery. Disease control was defined as a complete response (CR), which was seen in 3.2% of patients; a partial response (PR), seen in 46.1% of patients; or stable disease (SD), seen in 44.2% of patients. At a median follow-up of 10.0 months (interquartile range 4-22) after surgery, the median overall survival (OS) had not been reached in our cohort and median progression-free survival (PFS) was 9.0 months (95% CI 6.3-11.7). A CR or PR at first follow-up after surgery was associated with both a better OS and PFS compared to stable or progressive disease (p < 0.001). We conclude that selected patients can benefit from surgery after achieving disease control with systemic therapy

Surgery for Unresectable Stage IIIC and IV Melanoma in the Era of New Systemic Therapy

Opportunities for surgical treatment in metastatic melanoma patients have re-emerged due to the development of novel systemic therapeutics over the past decade. The aim of this study is to present data on outcomes of surgery in patients with unresectable stage IIIC and IV melanoma, who have previously been treated with immunotherapy or targeted therapy. Data was extracted from the Dutch Melanoma Treatment Registry (DMTR) on 154 patients obtaining disease control to systemic therapy and undergoing subsequent surgery. Disease control was defined as a complete response (CR), which was seen in 3.2% of patients; a partial response (PR), seen in 46.1% of patients; or stable disease (SD), seen in 44.2% of patients. At a median follow-up of 10.0 months (interquartile range 4-22) after surgery, the median overall survival (OS) had not been reached in our cohort and median progression-free survival (PFS) was 9.0 months (95% CI 6.3-11.7). A CR or PR at first follow-up after surgery was associated with both a better OS and PFS compared to stable or progressive disease (p < 0.001). We conclude that selected patients can benefit from surgery after achieving disease control with systemic therapy